“A serious comedy for trivial people.” — Oscar Wilde on “The Importance of Being Earnest.”

Confession. I have never read Jane Austen, but after spending two hours watching Whit Stillman’s film version of Austen’s novella “Lady Susan,” I’m convinced that Oscar Wilde was smitten with her from junior high on. “Lady Susan” is chock full of Wilde’s classic epigrams, with one big old Wilde-ish character dominating every scene he’s in. This would be the totally entertaining and welcome Tom Bennett as Sir James Martin, known to all who have experienced him as “a bit of a rattle.” Indeed. He’s keeps the film from sinking into too much Austen chatter. Chloe Savigny is charming and steady in her tight little role. Kate Beckinsale is all evil, sexy, conniving, manipulative and devious as Lady Susan. Did I forget anything?

Lady Susan, we learn, has a delicious habit of seducing men of standing, sucking up their money and juice, and then dropping them in to the dustbin of broken hearts. What’s worse, she can’t even keep them in mind.

When one of her old sweeties approaches her in the street, she dispenses him with “Who are you sir?” “Lady Susan, don’t you … .” “How dare you accost me in the street. Be gone or I will have you whipped.”

So much for the labors of love, sport.

Now the lady of the dark, recently widowed and adrift, is looking for cracks in the social canvass to find a suitable pair of husbands — one for herself, if you please, and one for daughter Francesca (Morfydd Clark) a teener of the time, so sweet we might suspect she’s someone else’s daughter.

Writer director Whit Stillman’s film is set, we discover at once, in “Mad George’s” regency period, when manners and proper credentials, not to mention the right livery on house staff, were everything, and in the words of our Billy Crystal, “It’s more important to look good than to feel good.”

It seems to have been very close to the jet set mores of the ’70s and ’80s on the sunlit beaches of Cannes and St. Moritz, when fading stars of entertainment and politics, still living off of their sunny times, “house jumped” from friend to friend, surviving on nibbling free snacks and drinks until their pasts caught up them. In Lady Susan’s case, it’s often explosive. That’s Noel Coward country.

I’m not fond of period pieces, with all of that fussy wardrobe and stuffy interiors. But Stillman seems to brighten things up here with a great British cast and a plot, by Jane Austen of all people, that rings like a SNL take on “Downton Abbey.” Stephen Fry, who has done a nifty Oscar Wilde in the past, is aboard with his usual stiff upper nose; and the aforementioned Tom Bennett, who thinks there were 12 commandments and is delighted to find there were only 10, two of which he can drop. What a great Algernon Moncrieff he would have been.

Stillman’s script is crackling with wit; the sets are lavish, overdone and occasionally drafty; and the costumes are befitting the age of regency. To Austen fans, “Love & Friendship” is not your grandmother’s Jane. Good show, Stillman.

J.P. Devine is a former stage and screen actor and author of “Will Write for Food.”